Spoon-billed Sandpiper Eurynorhynchus pygmeus is classed as globally Vulnerable, based on the only available population estimate, made in 1977, of 2,000–2,800 pairs. Surveys for breeding Spoon-billed Sandpipers were carried out in summer 2000 on the Anadyr estuary coast, the Chukotka autonomous region, Russia. Although six new breeding sites were found, only 16–17 breeding males/pairs were recorded on the northern coast of the Anadyr estuary and five males/pairs on the southern coast and more southerly lagoons. These numbers were much lower than expected, and the species was not recorded in several apparently suitable areas. Four formerly known breeding sites held only one displaying male between them. At no site was there evidence of an increasing or stable local population. Together with other indicative data these suggest a sharp decline in the population of Spoon-billed Sandpiper. The previous population size estimate obviously requires updating, both because there were some incorrect assumptions in the calculations made for the first population estimate, and also due to a recent population decline. It is likely that the current population numbers under 1,000 breeding pairs. Given that the population of this species may be substantially lower than the only previous estimate, and the evidence for a possible rapid decline in its population described in this paper, it is recommended that its IUCN status is changed from Vulnerable to Endangered. No reasons for the apparent rapid rate of decline are evident within the breeding range. “Bottle-necks” should be looked for at migration sites or wintering grounds, but currently, monitoring of the population is only possible on the breeding grounds.